charon-fan/documentation-engineer

Documentation Engineer

Expert in creating clear, comprehensive, and maintainable technical documentation.

When This Skill Activates

Activates when you:

• Ask to write documentation
• Request README creation
• Mention "docs" or "document this"
• Need API documentation

Documentation Types

1. README

Every project should have a README with:

# Project Name

Brief description (what it does, why it exists)

## Quick Start

Installation and usage in 3 steps or less.

## Installation

Detailed installation instructions.

## Usage

Examples of common usage patterns.

## Configuration

Environment variables and configuration options.

## Development

How to run tests, build, and develop locally.

## Contributing

Guidelines for contributors.

## License

License information.

2. API Documentation

For each endpoint/function:

• Description: What it does
• Parameters: Name, type, required/optional, description
• Return value: Type and structure
• Errors: Possible errors and conditions
• Examples: Usage examples

3. Code Comments

Comment why, not what:

// Bad: Sets the count to zero
count = 0;

// Good: Reset count for new measurement cycle
count = 0;

// Bad: Check if user is admin
if (user.role === 'admin') {

// Good: Only admins can bypass approval workflow
if (user.role === 'admin') {

4. Architecture Documentation

• System overview
• Component relationships
• Data flow
• Design decisions
• Trade-offs considered

Documentation Principles

1. Be Clear: Use simple, direct language
2. Be Concise: Respect the reader's time
3. Be Accurate: Keep docs in sync with code
4. Be Complete: Cover all public interfaces
5. Be Current: Update docs when code changes

Writing Guidelines

Headings

• Use sentence case for headings
• Start with a verb or noun
• Be descriptive

Code Examples

• Show before/after when appropriate
• Include import statements
• Show expected output
• Handle edge cases

Links

• Use relative links for internal docs
• Include anchors for sections
• Test that links work

Diagrams

• Use Mermaid for flowcharts and sequences
• Keep diagrams simple
• Add a title and legend

Documentation Checklist

README

• [ ] Project description
• [ ] Quick start guide
• [ ] Installation instructions
• [ ] Usage examples
• [ ] Configuration guide
• [ ] Contributing guidelines

Code Docs

• [ ] All public functions documented
• [ ] Parameters and returns documented
• [ ] Examples provided for complex functions
• [ ] Edge cases documented

API Docs

• [ ] All endpoints documented
• [ ] Request/response schemas
• [ ] Authentication requirements
• [ ] Error responses documented
• [ ] Rate limits documented

Scripts

Generate documentation structure:

python scripts/generate_docs.py

Validate documentation:

python scripts/validate_docs.py

References

• references/readme-template.md - README template
• references/api-template.md - API documentation template
• references/style-guide.md - Documentation style guide